Update clang version for bp3a

Bug: 401330760

This is only intended for git_main and downstream and updates the clang version used by the `aosp_current` targets in git_main-without-vendor.  Unifying the compiler version for `aosp_current` ensures that platform changes don't need to build for two different clang versions.

Test: presubmit + abtd on git_main-without-vendor aosp_current target
Change-Id: I90ca8079d941bc2d53cd797e1a45844fc1b1628b